Extension device



March 11, 1930. E. G. CARLSON 1,749,997

EXTENSION DEVI GE Filed Nov. 1928 I N V EN TOR. M2 63 ar/@019.

A TTORNEYS Patented Mar. 11, 1930 UNITED STATES PATENT OFFICE EDWIN G. CARLSON, OF RIVERSIDE, RHODE ISLAND, ASSIGNOR TO SPEIDEL CEAIN CO., A FIRM COMPOSED OF FREDERIC SPEIDEL AND EUGEN SPEIDEL, BOTH OF IPIBORZIH:EIJSIII, GERMANY, DOING BUSINESS IN PROVIDENCE, RHODE ISLAND foldable sections will be securely held against v nxrnivsion DEVICE Application filed November 1928. Serial No. 317,739.

This invention relates to a foldable extension device for enlarging the encircling length of a wrist band; and has for its Ob.

' ject to provide a construction by which the unfolding.

A further object of the invention is the provision of the cover section which is pivoted so that it will swing at right angles to the swing of the foldable sections and better hold the sections against an unfolding movement.

A still further object ,of the invention is the provision of adjustment for the encircling size of the strap at each end of the side sections, which .sections are of a combined length less than the body section so as not to overlap one another when in folded position.

invention consists of certain novel features of construction, as will be more fully described, and particularly pointed out in the appended claims.

In the accompanying drawings:

Fig. 1 is a top plan view of the strap of my extension device in folded position.

Fig. 2 is a bottom view of the extension device in the same position as Fig. 1.

Fig. 3 is a view similar to Fig. 1 looking at the top of the strap with the cover swung to open position.

Fig. 4: is a top plan view with the sections in unfolded position.

Fig. 5 is a section on line 5-5 of Fig. 1.

Fig. 6 is a'section on line 6-6 of Fig. 1.

Fig. 7 is a perspective view of the extension device detached from the straps and in open position.

It is found in the practical use of extension devices that they may under oppositely directed strains unfold orunclasp to the annoyance of the wearer; and in order to avoid this undesirable feature, I have provided a cover which swings at an angle to the swinging of the foldable sections to better resist such unfolding strains; and at the same time I have provided a pair of end sections which swing toward each other to substantially abutting relation and carry with them the With these and other objects in view, thestrap to which they are attached to hidev a large portion of the extension device from view when worn and by this construction the body of the extension device maybe made of a relatively long are shaped strip of metal and yet not be unsightly when in working position as the cover for holding these sections 1n folded position, which may be of comparatively small size, and may present the desired surface for ornamentation, is the only part visible; and the following is a detailed description of the present embodiment of this invention showing the preferred means by which these advantageous results may be accomplished:

With reference to the drawings, 10 designates one strap part and 11 the other strap part which parts are connected together by an extension device 13 comprising a body section 14 generally rectangular in shape with end sections 15 and 16 hinged thereto as at 17 and 18 to fold toward each other into the substantially abutting relation illustrated in- Fig. 3. Each of these end sections is provided with flanges or side walls 19 having a series of holes 20 in its opposite side walls to receive an attaching pin in-any selected position of adjustment for securing the tips 21 on the ends of the strap sections 10 or 11 thereto, it being understood that where different sizes of adjustment are desired the pin will be placed in different sets of openings, and the adjustment may be made from either or both of the ends as desired.

In order to secure the end sections in folded position, such as is illustratedin Fig. 3, I have provided a cover 23 hinged as at 24 to the side of the body section 14, the hinge 24: being arranged at rightangles to the hinges 17and 18 so that the swinging movement of the cover 23 is at right angles to the swin'gment with'the rib 28 formed on an outstanddo not overlap, and a cover carried by said in sheet metal wall 29 bent up from the other body section and hinged to swing at right si e of the body section 14 to releasably seangles to said end sectlons and over said end cure the cover in closed position. There is sections to hold them in folded position. sufficient resiliency between the wall 29 and 5. An extension device for a wrist strap the flange or side wall 26 of the cover to comprising a body section, an end section permit of a firm clasping relation of these hinged to each end of said body section to two parts so that lengthways strains upon fold thereover, and having strap end securthe strap will not serve to swing the end secing means at the free ends thereof, a cover tions on the body section or cause an opening carried by said body section and hinged to of the cover from its closed position. swing at right angles to said end sections and By arranging the cover to swing at right over said end sections to hold them in folded angles tothe end sections, the endways strains position, a flange on saidcover and cooperon the straps to swing them to open position ating means between said flange and body are better resisted and a more symmetrical sections to hold said cover in closed position. unfolding of the parts is provided whereby. 6. An extension device for a wrist strap the watch may be more easily positioned in comprising a body section, an end section the desired place on the wrist as may be rehinged to each end of said body section to quired. fold thereover, side walls on each end section, The foregoing description is directed solemeans to adjustably secure the strap between ly towards the construction illustrated, but I said side Walls, and means for securing said desire it to be understood that I reserve the sections in folded position. privilege of resorting to all the mechanical 7. An extension device for a wrist strap changes to which the device is susceptible, comprising a body section, an end section the invention being defined and limited only hinged to each end of said body section to by the terms of the appended claims. fold thereover, opposite side walls on each I claim: end section having a series of openings there- 1. An extension device "for a wrist strap, in and a pin in each of said sections to seleccomprising a body section and an end section tively engage said opening to adjustably sehin ed to each end of said body section to cure the strap en'ds thereto, and means for fohI thereover toward each other, each end securing said sections in folded position. section having opposed flanges at the free 8.' An extension device for a wrist strap end thereof, means extending between said comprising a body section, an end section flan es for securing a strap end thereto, the hinged to each end of the body section, said com ined length of said'e'nd sections being end sections folding together on the same no greater than the length of the body section side of the body section, side walls on each and end section, means to adjustably secure strap lded ends between said side walls, and means for securing said sections in folded position.

' In testimony whereof I afiix my signature.

EDWIN G. CARLSON.

whereby the end sections do not overla means for securing said sections in $0 position.

2. An extension device. for a wrist strap comprisin a plurality of sections hinged toether to fie folded one over the other or unfolded to extended position, the end sections having strap end attaching means at the free ends thereof, and a cover hinged to one of said sections to swin at right angles to the swingin of said sections and over said sections to hold them in folded position.

3. An extension device for a wrist strap comprising a body section, an end section hinged to each end of said body section to fold thereover, and having strap end securing means at the free ends thereof, and a cover carried by said body section and hinged to swing at right angles to said end sections and over said end sections to hold'them in folded position.

4. An extension device for a wrist strap comprising a body section, an end section hinged to each end of said body section to fold thereover toward each other, and having strap end securing means at the free ends thereof, the combined length of said two end sections being no greater than the length of said body section whereby the end sections 

